Not all data sources will support a catalog, or the data sources may return a catalog name that is not useful. For example, Microsoft Access returns the full path to the database, which is not needed since this information is detailed in the datasource.
The default behavior of the runtime is to not use the catalog in the actual SQL queries. This configuration variable enables you to modify this behavior. The default value is FALSE, which causes the catalog portion of the table name to be treated as blank in SQL queries. Setting this variable to TRUE causes the value of the catalog returned by SQLTables ODBC function to be used in subsequent SQL queries.
See also: USER_PATH (for DB2) configuration variable, USER_PATH (for Oracle) configuration variable, and A_ODBC_CATALOG